Magnetic separator



(No Model.)

T. A. EDISON.

MAGNETIC SEPARATOR.

No. 430,275. Patented June 17, 1890.

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UNITED STATES PATENT OFFICE.

THOMAS A. EDISON, OF LLEl/VELLYN PARK, NEW JERSEY.

MAGNETIC SEPARATOR.

SPECIFICATION forming part of Letters Patent No. 430,275, dated June 17,1890.

Application filed September 20, 1888. Serial No. 285,923. (No model.)

To all whom it may concern.-

Be it known that I, THOMAS A. EDIsoN, of Llewellyn Park, in the countyof Essex and State of New Jersey, have invented a certain new and usefulImprovement in Magnetic Separators, (Case No. 799,) of which thefollowing is a specification.

The object of my invention is to effectively separate magnetic fromnon-magnetic materials; and my invention consists in certainimprovements on the apparatus for this purpose set forth in my patent,No. 228,829, datedv June 1, 1880. Vhen the mingled body of magnetic andnon-magnetic materials which is to be acted upon by the magnet containsa great many particles of very light substance, as is the case withcertain iron ores which contain light particles of phosphorus andsilicon ores, it is extremely difficult to effecttively separate suchlight particles from the magnetic material, because they are affected bycurrents of air, and so may float or be carried into the receptacle forthe magnetic particles, whereby the product is rendered impure andunavailable for the Bessemer process. By my present invention I providemeans for obviating this difficulty. I employ for this purpose a gentlecurrent of air affecting the stream of materials as it falls from r thehopper, whereby the extremely light par ticles are separated from therest and directed into a separate receptacle which is provided for them.

Another feature of my invention consists in the employment of anopen-end magnet or a bar-magnet, in connection with means for directingan air-current against the falling material, as willbe described. I findthat this is exceedingly advantageous in the process of separation,because where a horseshoe-magnet is used its magnetic field is small andconcentrated, and does not include a large quantity of the material,whereas with the bar-magnet the magnetic field is very much spread outand acts upon-the falling stream throughout a large part of its extent,and the impressed magnetism on the magnetic ore, while sufficient toalter its trajectory, is at no time during its fall of sufficientstrength to cause such particles to mutually attract each other, andthus lock the non-magnetic particles between the magnetic particles,which would make the product too rich in phosphorus or other foreignmaterials for the Bessemer process.

My invention is illustrated in the accompanying drawings.

Figure 1 is a vertical section of and partial side elevation of themagnetic separator embodying my invention, and Fig. 2 is a perspectiveview of the same.

I employ a hopper A, of the kind set forth inmy application filed March29, 1888, Serial No. 268,749that is, one havinga flat bottom containinga long narrow aperture or a long row of small holes through which thematerial falls in a wide thin stream. tance below the hopper is placedthe magnet B, which is a wide fiat bar-magnet whose pole extends thewhole width of the stream which falls from the hopper.

O is a pipe which extends from a suitable fan or blower adapted toproduce a gentle current of air-. This pipe is divided into two branchpipes D and D. Pipe D extends beneath the hopper a short distance belowit and terminates in a long cross-pipe E, which extends the whole widthof the hopper, and is provided with an aperture or series of aperturesthrough which the current of air is directed against the fallingparticles. The pipe D extends below the magnet 13 and terminates in across-pipe E, whereby the air-current is also directed against thefalling particles at this point. On the other side of the opening in thehopper and just below the pipes D and D ,I provide inclined partitionsFand F. It will be seen that as the stream of mingled magnetic andnonmagnetic particles falls from the hopper the air-current from thepipe E will separate from it the very light nonmagnetic particles, andthese will pass to the left of the partition F and fall into thereceptacle formed by said partition. Any light particles which are notremoved at this point will receive the air-current from the pipe E andbe blown past the partition F. The magnet B, as will be well understood,alters the direction of falling of the magnetic portion of the material,so that it falls to the right of the partition G, while the non-magneticparticles, which are too heavy to be affected by the air-current, willfall vertically from the hopper into the space between par- A shortdistitions F and G. The widely-diffused magnetic field of the bar-magnetacts upon the material more effectively than the concentrated field of ahorseshoe-magnet, as already explained.

The dotted lines in Fig. 1 illustrate a modification of my invention. Anair-tight chamber is provided with an opening in proximity to thefalling stream, and a pipe H leads from this chamber to an exhaustingapparatus. Air being constantly withdrawn from the chamber, theair-current produced by the suction acts upon the light particles anddraws them into the chamber. The chamber between partitions F and G mayalso be made air-tight and provided with an exhaust-pipe with a similarresult.

What I claim is 1. In a magnetic separator, the combination, with thehopper and the magnet for altering the trajectory of the magneticmaterial, of means for producing an air-current acting upon the fallingmaterial, substantially as set forth.

2. In a magnetic separator, the combination, with the hopper and themagnet for altering the trajectory of the magnetic material, of meansfor directing an air-current against the falling material, substantiallyas set forth.

3. In a magnetic separator, the combination, with the hopper and themagnet for al tering the trajectory of the magnetic material, of theinclined partition and. the air-pipe for directing a current of airagainst the falling material, substantially as set forth.

4. In a magnetic separator, the combination of the hopper having anopening through which the material falls in a wide thin stream, themagnet below the same for altering the trajectory of the magneticmaterial, and the air-pipe placed parallel with the fallin g stream,whereby the air-current is'directed against the full Width of thestream, substantially as set forth.

5. In a magnetic separator, the combina: tion, with a hopper and abar-magnet for altering the trajectory of the magnetic material, ofmeans for directing an air-current against the falling material,substantially as set forth.

This specification signed and witnessed this 12th day of September,1888.

THOS. A. EDISON.

Witnesses:

WILLIAM PELZER, A. W. KIDDLE.

